Recently, a gallium nitride based light emitting diode (LED) die have been increasingly used as a light source. The optical power of such a light emitting diode is generally proportional to a magnitude of an input current. Accordingly, if the magnitude of the input current supplied to the light emitting diode is increased, high optical power can be obtained. However, the increase in the magnitude of the input current causes the junction temperature of the light emitting diode to increase. The increase in the junction temperature of the light emitting diode causes a photometric efficiency to be reduced, wherein the photometric efficiency indicates what portion of an input energy is converted into visible light. Accordingly, it is required to prevent the increase in the junction temperature of the light emitting diode due to the increase in the magnitude of the input current.
Conventionally, in order to prevent junction temperature of a light emitting diode from being increased, a package has been used in which a heat sink is coupled to a lead frame to thereby dissipate heat through the heat sink. However, since the package is manufactured by coupling a separate heat sink to the lead frame, there is a problem in that a structure of the package and therefore a process of manufacturing the same may be complicated, and thus, the manufacturing cost of the package may be increased.